Introduction to Psychological Science: Integrating Behavioral, Neuroscience and Evolutionary Perspectives - William J. Ray 2021

Learning, Ethology, and Language Processes

LEARNING OBJECTIVES

✵ 8.1 Describe the basic processes of classical conditioning.

✵ 8.2 Describe the basic processes of operant conditioning.

✵ 8.3 Summarize the types of learning that occur during imprinting, play, observational learning, and imitation learning.

✵ 8.4 Describe how we learn languages.

✵ 8.5 Identify the parts of the brain that are active in language processes.

One classic study in fear learning is that of Susan Mineka and her colleagues (see Öhman & Mineka, 2001, for an overview). It had been observed that primates in the wild show a fear of snakes. Since a similar fear is seen in lab monkeys, it was assumed that the fear was somehow innate. However, Mineka asked the question of whether early experience could influence this. In particular, she wanted to know if learning could play a role.

What she and her colleagues did was to compare wild-reared rhesus monkeys with those that had been reared in the lab. The wild-reared monkeys that had been brought to the lab some 24 years earlier showed a fear of snakes. This fear existed even though they would have had no experience with snakes during their time in the lab. The lab-reared monkeys, on the other hand, did not show any fear of snakes. In fact, they would reach over the snake to grab food.

How did monkeys develop the fear of snakes? What Mineka did next was to pair a wild-reared monkey with a young lab-reared one. A snake was then presented, and a wild-reared monkey showed fear. The young lab-reared monkey was able to observe this. After this, the lab-reared monkey also showed fear. Clearly, the lab-reared monkey had the ability to quickly learn the fear but required an experience in which another monkey showed fear for it to happen. The next question Mineka and her colleagues asked was the importance of the feared object itself.

In a very clever study, she showed some of the young monkeys a videotape of a wild monkey showing fear toward a snake. As expected, they learned the fear of snakes. However, with another group of young monkeys, she edited the tape so what the young monkey saw was the original fear reaction of the older monkey but this time to a flower. If fear was acquired by a simple learning process in which the stimulus did not matter, then you would expect the young monkeys to learn a fear of flowers. However, the monkeys did not learn to fear flowers. Thus, the nature of what the monkey sees is important. In the real world, snakes but not flowers can be dangerous.

Although most of us have an idea of what it means to learn something, learning is actually a difficult and complex concept to define. In fact, it has been pointed out that the definition of learning differs across different areas of study including psychology (Barron et al., 2015).

B. F. Skinner, who supported a behaviorist view of psychology in the last century, suggested that learning should be defined as behavior change, that is, a change that can be seen. Skinner emphasized the modification of behavior in which a response followed by a reward will be increased. This came to be called operant conditioning, which is a special type of learning. Skinner saw almost all human behavior, including the learning of language and the development of mental disorders, as controlled by the laws of learning based on external rewards. Today, we know that conditioning is only one type of learning. Overall, learning is influenced by both external processes such as rewards and internal processes such as previous memories or preparedness. The stages of language learning in children is an example of learning that takes place as the brain develops or is prepared for its occurrence.

Almost every chapter in this book describes changes in behavior. These changes in behavior can come about by being with others, changes in motivation, feeling tired, or experiencing mental disorders. Thus, not every change in behavior involves learning. We need to remind ourselves that learning is not a simple process that just changes behavior. We can define learning as the acquisition of knowledge or skills through experience, study, or by being taught.

So far in this book, you have seen how learning to play a musical instrument or learning the taxi routes of London can change your brain. You have also seen the research of Eric Kandel, who showed that learning affects neural connections in the brains of sea slugs. Piaget showed that learning takes place in an interaction with the environment. However, a child must be in a specific stage of development before this learning can take place. Likewise, leaning language is easier at some stages of development than others. Whereas language learning is what every child does, learning to read or write takes more effort. Learning math is also a more difficult task. As you will see, ease of learning is related to our evolutionary history.

Since the time of Darwin, learning has been considered an important mechanism by which an organism adapts to changing environmental conditions. In this sense, learning is part of the human processes that use our past experiences to predict what will happen in the future (Bar, 2011). You just read that young monkeys who were not afraid of snakes learned this fear just by watching another monkey show fearful behavior. However, the monkeys did not learn to be afraid of flowers. This suggests that learning takes place in a context related to our evolutionary history. That is, some information is more important to us than other information. This is especially true of information that can help us survive. Snakes are more likely to harm us than flowers. Thus, our evolutionary history influences what and how we learn.

This chapter will introduce you to some of the ways that learning has been studied. In the beginning and middle of the last century, learning studies were strongly influenced by behaviorism. Behaviorism stressed external factors and ignored internal processes. This led to a view of humans as passive and basically the result of rewards in their lives. This chapter will include historical views of conditioning as well as the manner in which research has expanded our view of learning. The development of cognitive psychology in the 1960s greatly expanded the behaviorist view.

Not only can learning be rapid, but it can also be part of a normal pattern of development. As you will see, naturalistic research emphasizes the natural environment of the organism, whereas Skinner had created an artificial one. Both humans and other animals can learn simply by observing the action of others. We as humans are actively involved in perceiving, acting, and increasing our understanding of new information. This chapter will end with a discussion of the most natural learning of all, that of language. Language is critical for humans as it allows us to reason, solve problems, and have social relations with others. These aspects of our cognitive processes will be discussed in later chapters.

In this chapter, you will see that some learning can happen quickly, whereas other learning can take a long time. You will also see that some learning can happen naturally, as with the case of learning a language as a child. Other learning, such as memorizing the names of chemical elements or stars, requires more effort and practice. We can also learn just by watching someone perform an action. We know that many animals learn by just watching other animals. By the way, humans are the only species that has developed institutions that are specifically designed to teach and transfer information. In order to understand one aspect of learning, that of conditioning, let’s begin with two basic learning mechanisms—classical conditioning and operant conditioning.

Classical Conditioning

Perhaps you have started to open a pet food can to feed your pet, and all of a sudden your pet is there. Waiting to be fed. How did this happen? Of course, your pet may have smelled the food even if you could not. However, often your pet is there before the can is opened. As a psychologist, you might want to know what mechanisms are at play to bring your pet to you as you open the can. How did your pet learn this? It is through the mechanism of classical conditioning.

Classical conditioning was first described at the turn of the last century by the Russian physiologist Ivan Pavlov. After studying physiology and medicine in St. Petersburg, Russia, Pavlov became the director of a new laboratory for animal experiments in 1879. Pavlov was particularly interested in the body as a whole and the manner in which all of the parts worked together (Paré, 1990). As such, his was an early emphasis on homeostasis, the manner in which the body stays in equilibrium. Pavlov was also influenced by Darwin and sought to understand the mechanisms by which animals adapt to their environment. His early research focused on the heart and digestive system. He was awarded the Nobel Prize in 1904 for his work.

Pavlov believed that the nervous system controlled all body systems, and he sought to determine how the secretion of gastric juices was controlled by neural reflexes. This led him to show that food will produce gastric juices even if the food never enters the stomach. In fact, working with dogs, he was able to show that just the sight of food would produce saliva in the mouth.

Pavlov referred to these as psychic secretions, since there was no physical connection between the food and the salivation. Pavlov saw the salivation as the result of a reflex that involved the brain and referred to the process as a conditional reflex. The term was mistranslated into English as conditioned reflex, a mistake that helped create the terminology we currently use to describe classical conditioning. His lab began to systematically study this process.

Classical conditioning is the process in which two stimuli become associated with each other (see Gottlieb & Begej, 2014 for an overview). One of these stimuli, such as food, will produce a natural response, such as salivation. That is, animals consistently respond to food with salivation. In this case, salivation is referred to as the unconditioned response (UCR). Because the food stimulus will consistently produce a response, it is technically referred to as an unconditioned stimulus (UCS).

In the studies of classical conditioning, it was noted that events that happened at about the same time as an unconditioned stimulus could themselves produce a response. For example, the dogs in Pavlov’s lab might hear the door opening or the footsteps of the person who fed them. In themselves, neither the sound of a door opening nor the sound of footsteps would produce salivation. However, when the sounds were paired with the food given to the dogs, after a time, the sounds alone produced salivation. These types of events are referred to as conditioned stimuli (CS). Technically, we say that if the unconditioned stimulus is paired with the conditioned stimulus, then after a number of times of pairing, the conditioned stimulus alone will produce the natural response. This response is referred to as a conditioned response (CR).

The process of pairing a UCS and a CS is referred to as acquisition. As you can imagine, the strength of the CR will be less if it has been paired with the UCS only a few times as opposed to many times. Thus, if you were to ring a bell just before you introduce food to the dog only once, the bell alone would probably not produce much in the way of salivation. However, if you were to pair the ringing of the bell with the food a large number of times, then the bell alone would produce salivation (see Figure 8-1).

Figure 8-1 Graphic of conditioning process.

Once the bell alone would produce salivation, what do you think would happen if you rang the bell a number of separate times without the presentation of food? That’s right, although initially the bell would produce the salivation, this response would change over time. As one continued to ring the bell without the pairing with food, the salivation response would decrease and eventually disappear. The process is referred to as extinction. Extinction happens when the CS is presented alone. What if you waited a day or two and rang the bell again? A surprising thing will happen. Salivation will again appear. This is referred to as spontaneous recovery.

Classical conditioning can work with any naturally occurring physiological process. Food is a classic example. However, in adapting to changing environments, you would not only want to learn about things that were positive for you, but also those that you might want to avoid. For some people just hearing the sound of the drill in a dentist’s office will produce a response. Likewise, if a puff of air is released near your eye, you blink. Researchers have used such unconditioned stimuli as a small shock or puff of air to study classical conditioning. Thus, the principles of classical conditioning work equally well both with emotionally positive and negative stimuli.

Conditioning in Your Daily Life

You might think that classical conditioning is just an academic topic. However, if you look at the advertisements you see every day, it becomes apparent that it is all around. You begin by asking the question what has emotional positive connotations for humans. Food, sexuality, and friends are three such unconditioned stimuli. Many beer ads will feature a sexually suggestive scene (the unconditioned stimulus) paired with a particular brand of beer (the conditioned stimulus). Other ads may show a dog or other animal that provokes an emotional response (unconditioned stimulus), which is paired with a particular brand of car or other product (conditioned stimulus). For many of us, these pairings take place completely out of our awareness. Typically, advertisers seek to find images that produce instinctual responses in their targeted consumer such as an attractive person. Another everyday example of conditioning involves drug reactions as described in the box: The World Is Your Laboratory: Reactions to Addictive Drugs.

Drug Reactions

The World Is Your Laboratory: Reactions to Addictive Drugs

Initially, professionals who worked with those addicted to drugs were surprised to see physiological changes as the person was only preparing to take the drug. That is, as a person prepares his heroin dose, his body showed a physiological reaction. Even stranger was that the person showed reactions that were opposite to the normal effects of the drug. What we now know is that these opposite responses were the body’s way to prepare for the negative effects of the drug.

One important way of understanding the factors associated with drug use is through the principle of classical conditioning (Siegel, 2008; Siegel & Allen, 1998). From this standpoint, the direct effects of the drug would be considered the unconditioned stimulus (US). The cues associated with the primary effects would be the conditioned stimuli (CS). Over time, making a cup of coffee, opening a bottle of wine, rolling a joint, or preparing cocaine can, through classical conditioning, bring forth a reaction before the drug is actually consumed.

Further, the effects of many drugs decrease as one uses the drug more frequently. This is referred to as drug tolerance. For example, those who smoke or use alcohol frequently will not experience the same effects that they initially did. This phenomenon also has a learning effect. This is particularly true if the person takes the drug in the same environment under the same conditions.

What would happen if the person took the drug in a totally different situation? It is almost like the person is taking the drug for the first time. In novel environments, the effect of the drug becomes stronger. It is suggested that this results from the fact that cues traditionally associated with the administration of the drug are not there. In fact, it has been shown that if an opiate is given through an intravenous infusion in which the subject cannot know whether administration is taking place or not, the tolerance effect will not be seen. Giving the opiate through an injection would produce tolerance effects. Likewise, college students who drink will show greater tolerance to the intoxicating effects of alcohol when consumed in beer than if the same amount of alcohol is consumed in a blue, peppermint-flavored beverage (Siegel, 2005). That is, the traditional consumption of alcohol in beer is well known. Consuming alcohol in a blue, peppermint-flavored beverage is novel and strange and the traditional learning effects are not experienced.

Using these learning principles can help us understand a number of factors related to drug use. One of these is why individuals who have given up an addictive substance such as alcohol or tobacco will experience craving when placed in situations in which these drugs were previously used. Just seeing the items associated with drug use can bring forth these cravings. Further, in certain novel situations, the effects of the drug can be stronger than normal (Siegel, 2001). Thus, someone can experience an overdose by first developing tolerance to a drug in a familiar situation. This tolerance may be associated with an increase in the amount of the drug to counter the effects of tolerance. However, if the person is to use the same amount of the drug in a novel situation, an overdose can be experienced. The result is that the overdose is more associated with the external and internal cues of the situation than the actual amount of the drug used. Thus, to be effective, drug treatments need to consider both the external and internal cues associated with the use of the drug by extinguishing these associations.

Thought Question: What are three specific take-aways from this feature that help you understand drug addiction and its treatment better?

Emotional Conditioning

John Watson, whom you met in Chapter 1, emphasized psychology as the study of behavior. He further emphasized behavior as the result of learning. That is, Watson wanted to show that seemingly complex behaviors such as phobias could be the result of simple conditioning. In order to do this Watson worked with a normal 9-month-old child named Little Albert. The child initially played with whatever animals he was shown—a rabbit, a white rat, a dog, and so forth (as shown in Figure 8-2). In the classic case study of Little Albert, John Watson, in the 1920s, showed that animals that the child had previously played with happily could, through classical conditioning, come to be feared (Watson & Rayner, 1920).

Figure 8-2 Nine-month-old Little Albert, John Watson, and Rosalie Rayner initially playing with animals.

The conditioning procedure was to pair a loud noise with the animal. The loud noise itself (produced without warning by hitting a steel bar with a hammer) would produce a fear response. This loud sound was made when the animal, such as a rabbit or white rat, was with the child. After the pairing the animal with a loud sound, the child would withdraw. As a result, Little Albert showed fear when in the presence of these animals, even without the loud sound.

Initially, Little Albert was conditioned by pairing a white rat and a loud noise. After this, any furry animal such as a rabbit would produce the same fear response. This is referred to as generalization, first noted by Pavlov in his work with dogs. It should be noted that the less the stimulus is like the original conditioned one, the less intense the conditioned response will be. That is, if the original stimulus was a 10,000 hertz tone, for example, then tones of 8,000 hertz and 12,000 hertz would produce larger responses than those of 4,000 hertz or 16,000 hertz. The more similar the new stimulus is to the original conditioned one, the stronger the response. In Little Albert’s case, a furry bunny is more like a white rat than is a ball of yarn. However, we now know that learning takes place in relation to our evolutionary history.

Watson’s demonstrations with Little Albert appear in many introductory psychology textbooks. However, what is often left out is the finding that fear conditioning worked better with evolutionarily relevant objects such as animals but less so with a bag of wool or with person-made objects such as a wooden toy (cf. English, 1929; Watson & Rayner, 1920). In short, we are biologically “primed” to learn to fear animals or situations that could truly threaten us, and not “primed” to be conditioned to fear inanimate objects.

Fear conditioning in both humans and other animals serves a critical role in helping organisms detect and respond to threat. Learning which situations are dangerous and which are not is critical to survival. However, the fear response can be generalized to situations that are not dangerous. Often children who are stung by a bee will try to avoid any insect with a similar buzzing sound. Freud discussed how being in an automobile accident could result in a person being afraid of future car rides or even situations associated with the previous accident. If this type of generalization to other similar situations continues for a long time, then this can cause problems in human functioning that limit one’s response by making safe situations seem dangerous. Since humans also make cognitive inferences concerning their behavior, the interpretation of fearful events can go beyond the principles of classical conditioning (Dunsmoor & Murphy, 2015).

Garcia Effect and Food Aversion

Another type of learning that does not follow simple conditioning procedures is food aversion. Have you ever eaten something that made you sick, and for the next few years you couldn’t stand the sight of that food? For some, it is fish, for others it is chicken salad, or for some it can even be green Jell-o. From an evolutionary perspective, this is a critical mechanism. To learn quickly that a food is bad for you could prevent you from experiencing a number of trials until you learned that a certain food was bad for your health. Over evolutionary time, this mechanism would have allowed all types of species to adapt to their environment.

What is amazing about this type of learning is that it is so quick. It only takes one pairing of the food and nausea. What is also different than traditional conditioning procedures is that the response of feeling sick may come some hours after actually eating the food. Future situations with the food only require that you see or smell the food. You do not actually have to taste it. In fact, the aversion is so strong for most people that they will refuse to be around the food.

The nature of learning food aversion may initially seem like classical conditioning, but it does not follow normal conditioning procedures. With Pavlov’s techniques, it would take a number of trials for the bell or other conditioned stimulus to be associated with the food. Food aversion takes only a single trial to be learned. With traditional classical conditioning techniques, the pairing of the UCS and the CS must be close to each other in time. Otherwise, classical conditioning will not take effect. This was an upsetting fact to many researchers when taste aversion was initially studied in animals since ideas concerning evolutionary preparedness were rarely considered.

One of the early researchers in the 1950s to study taste aversion was John Garcia (1917—2012). In fact, the phenomenon of taste aversion is often referred to as the Garcia effect. In an important paper that appeared in the journal Science, Garcia and his colleagues showed that rats, when given a saccharin solution paired with a radiation procedure that would make them sick, would avoid saccharin water some days later (Garcia, Kimeldorf, & Koelling, 1955). The actual study paired a procedure with no radiation or different levels of radiation with the saccharin tasting water. Three days later a regular bottle of water and a bottle of saccharin water were put in their home cage and the amount consumed daily was measured for two months. It was found that the rats who received the radiation avoided the saccharin water relative to how much radiation they received.

Today, health care professionals are paying attention to those receiving radiation and other treatments for cancer (Kusnecov, 2014). That is, they are seeking to condition a non-normal taste to the radiation rather than the foods that the person likes the best. In this way, the cancer treatment will not negatively influence through conditioning the pleasant aspects of a person’s life.

Conditioning and the Brain

Eric Kandel, to whom you were introduced in the introductory neuroscience chapter, set out to understand how learning and memory were represented in the brain. As you remember, he chose the California sea slug Aplysia to study. Although this sea slug is complicated in many ways (for example, they can be both male and female as needed), it does have a simple reflexive behavior—the withdrawal of its gill. The gill is an external organ that the sea slug uses to breathe. Touching the gill causes it to withdraw.

It turns out that this gill reflex is similar to a number of responses in humans. For example, the first time you hear a clock tower chiming or a train going by your house, it seems loud. However, after a time, your response decreases as the sound is repeated. Technically, this process is referred to as habituation. Habituation is the situation in which a reflexive action decreases with repeated presentation of the stimulus. Why would we want to habituate to a repeated stimulus? Exactly, because its repeated occurrence carries with it no new information. The first time we experience it, it could be signaling danger or other information important to our existence. We may need to adapt to protect ourselves. However, once we know we are not receiving new information, there is no need to respond. This is part of our evolutionary history in which organisms use their energy for events that are important and reduce their energy expenditure for those that are not. Habituation is thus a natural response for regulating our cognitive and emotional energy.

What Kandel and his colleagues did was to focus on a critical synapse. This synapse was located between the neuron that brought sensory information related to being touched and the motor neuron that caused the gill to withdraw. What they discovered was that with repeated stimulation, habituation took place, and the sensory neuron released less neurotransmitter. The neurotransmitter involved was glutamate—the major excitatory neurotransmitter in our brain. Less of the neurotransmitter glutamate reduces the chance that an action potential will be produced.

The opposite of habituation is sensitization. For example, if you receive a painful shock, then the next shock would result in a greater response in a number of different systems. The shock could, for example, make a noise seem louder. Kandel and his colleagues found that sensitization results in a greater level of glutamate at the synapse. Thus, this increases the chance that an action potential will be produced. In other studies, Kandel showed that when experiences become part of long-term learning and memory, the connections at the synapse are increased. This shows that with learning the brain changes (see Kandel, 2006 for an overview).

After nearly a century of research using classical conditioning, the manner in which the brain is involved in conditioning, particularly fear conditioning, has been determined (Pellman & Kim, 2016). The general picture is that information related to the conditioned stimulus is processed in the amygdala. This information is then connected with the unconditioned stimulus to create a relationship. The amygdala also has strong connections to the hippocampus, which plays an important role in episodic memory. The hippocampus not only is related to memory but also the location in which an event took place, referred to as spatial memory. Cognitive processes along with habituation can be used to treat learned aversions, as shown in the box: Applying Psychological Science: Fear of Flying.

Applying Psychological Science: Fear of Flying

More than one in ten people have a fear of flying (Oakes & Bor, 2010). As would be expected, the initial increase in cases of reluctance to fly began to develop in World War I with the development and use of airplanes for observation and warfare (Laker, 2012). This is reasonable on a risk basis since warfare includes destruction and death. Also, stress factors on materials used to make airplanes were not well understood during the early part of the 20th century, resulting in a number of accidents. Today, the factors that increase airline safety are better understood. In fact, today it is riskier to take a trip in an automobile than one in an airplane.

Since flying in an airplane is a relatively new experience for humans, there is little reason to suggest a direct evolutionary link to the fear of flying. Of course, indirect relationships to self-preservation can play a role. However, fear of flying is not associated with other phobias such as a fear of elevators. It is assumed that fear of flying is learned. Further, the fear can be related to observation learning or other learning mechanisms if the person has experienced others around her showing fear in the presence of taking an airplane trip. This suggests that learning procedures centered on the extinction of responses could play a role in reducing the fear of flying.

One treatment approach that you will learn more about in the chapter on treatment of psychological disorders is systematic desensitization, which is based on classical conditioning procedures (Wolpe, 1958). The basic idea is that fear responses have become connected with events that are not fear-producing in themselves. For example, for some people seeing a physician in a white coat will result in increased emotional reactions associated with anxiety. Classical conditioning works in a similar manner to that of Pavlov’s dogs in that the white coat becomes associated with other events that lead to emotional arousal.

Systematic desensitization works by pairing the emotionally arousing object or event with relaxation. Wolpe suggested that you cannot be relaxed and afraid at the same time. Thus, the procedure was to teach someone relaxation and then to pair the relaxed state with that of an anxiety-arousing situation. In the case of fear of flying, a person would construct a hierarchy of fear beginning with the least arousing situation and ending with the most arousing one. As illustrated in the list below, the person would enter a relaxed state and then imagine seeing an airplane in the sky. If she was able to remain relaxed as they considered that situation, she would then move on to the next situation. If she became anxious, then she would move back in the hierarchy until she could achieve a relaxed state.

✵ Fear of flying:

o Seeing an airplane overhead

o Driving to an airport

o Walking into the terminal

o Waiting for an airplane

o Entering the airplane

o Sitting down

o Buckling the seatbelt

o Feeling the airplane move

o Taking off

Since the time of Wolpe, a number of modifications have been made to these procedures. One is the use of virtual reality as well as airplane sounds to give the person a heightened experience of the anxiety-producing situation (Brinkman, van der Mast, Sandino, Gunawan, & Emmelkamp, 2010). Currently, a number of airlines around the world offer courses in which the anxious individual goes through actual situations similar to the previous hierarchy. Using classical conditioning techniques, these airlines will pair pleasant situations such as eating food or candy with the airport and flying experience. Additionally, many of these programs add a cognitive component to help the person reinterpret the anxiety-arousing event. For example, when an airplane initially takes off, power to the engines is increased. About ten seconds after takeoff, the power to the engines is decreased. This is experienced initially as if the plane is standing still. Without this knowledge, the person may think the plane will fall and become anxious. Knowing this, the person can reinterpret her initial fear and see it as a normal part of flying. Overall, techniques based on learning and extinction principles have been shown to be effective in reducing a person’s fear of flying (Laker, 2012).

Thought Question: Suppose you have a fear of public speaking. Construct for yourself a hierarchy of fear beginning with the least arousing situation related to public speaking and ending with the most arousing one.

CONCEPT CHECK

1. Define and describe the relationships between the following concepts in classical conditioning:

a. Unconditioned stimulus (UCS) and unconditioned response (UCR)

b. Unconditioned stimulus (UCS) and conditioned stimulus (CS)

c. Conditioned stimulus (CS) and conditioned response (CR)

2. What is the role of the following processes in classical conditioning:

a. Extinction

b. Spontaneous recovery

c. Generalization

3. What do Watson’s experiments with Little Albert illustrate about the role of evolution in classical conditioning of fear? What types of experiences are we “primed” to fear? How can the concept of generalization lead to problems in human functioning?

4. What is the process of learning a food aversion? How is it different from classical conditioning? How is the process beneficial in an evolutionary sense?

5. How was it discovered that the immune system itself could be conditioned? What is an example of when that conditioning would have a negative effect? What is an example of when that conditioning would have a positive effect?

6. What roles do habituation and sensitization play in learning from an evolutionary perspective? What specifically happens in the brain as a result of these two processes?

Operant Conditioning

What if you wanted to teach your dog to perform a certain trick? Perhaps you wanted your dog to roll over or jump over a small fence. How would you do that? One approach is to give your dog a treat after it performed the behavior. In this case, your dog would be producing a behavior for a reward. Formally, this type of learning is referred to as operant conditioning.

Operant conditioning, also called instrumental conditioning, is the type of learning in which the frequency of the behavior is controlled by its consequences (see Murphy & Lupfer, 2014 for an overview). The behaviors that an organism performs are referred to as operant responses. The term “operant” is the combination of two terms, “operate” and “environment.” Thus, they are behaviors that operate on the environment to produce consequences. In the case of your dog, the consequence was receiving food.

Thorndike and the Puzzle Box

Before operant conditioning received its name, Edward Thorndike (1874—1949) began studies of how animals solve problems and learn. This was about the same time as Pavlov’s work. What Thorndike did was to place an animal such as a cat in what came to be called a puzzle box. The box was designed so that the cat could open the box by performing a particular action such as stepping on a lever or pulling a rope that would open the door. Outside the box was a bowl of food. Since the animals had not been fed before they were put in the box, the hungry animals sought ways to get to the food.

As you can imagine, the cat would initially engage in behaviors such as pushing on the bars, allowing them to eat the food. After trying a large number of behaviors that did not result in opening the door, the animal would finally engage in the behavior that did result in the door being opened. At this point the animal had access to the food. Thorndike repeated this procedure a number of times to determine how the animals learned. In the first few trials, the animals would engage in different series of behaviors until they were able to open the door and get to the food. By 20 or 30 trials, the animal was able to open the door as soon as it was placed in the puzzle box.

Based on his research Thorndike was able to influence the study of learning in two ways. First, he formulated his law of effect. The law of effect says:

Of several responses made to the same situation, those which are accompanied or closely followed by satisfaction to the animal will, other things being equal, be more firmly connected with the situation, so that, when it recurs, they will be more likely to recur; those which are accompanied or closely followed by discomfort to the animal will, other things being equal, have their connections with that situation weakened, so that, when it recurs, they will be less likely to occur. The greater the satisfaction or discomfort, the greater the strengthening or weakening of the bond.

(Thorndike, 2011, p. 244)

That is, when the cat made a response that led to the opening of the door and food (the satisfying effect), then the cat would be more likely to perform that same response again. The opposite is also true. If the response produces discomfort, then those responses will be reduced. The second way Thorndike influenced the study of learning was to graph the animal’s response, which is referred to as a learning curve. Learning will be described in the next section with the work of B. F. Skinner.

B. F. Skinner and Operant Conditioning

B. F. Skinner (1904—1990) was the person who most influenced the study of learning in psychology during the middle of the last century. Like Watson, Skinner believed that psychology should only study behaviors that could be observed. In particular, the goal of psychology should be the prediction and control of behavior. As such the emphasis was on data rather than theory.

Skinner coined the term operant behavior to refer to the behavior that an organism produces that influences its environment. He also suggested the term reinforcer or reinforcement be used rather than satisfaction as with Thorndike’s law of effect. This was to avoid any reference to the inner processes of the organism. Thus, an organism emits behaviors that influence the environment. If the behavior (for example, pressing a bar) is reinforced (for example, receiving food), then its occurrence will increase.

Figure 8-3 Skinner box—the animal presses a lever to receive food.

In order to study learning, Skinner developed a simplified version of Thorndike’s puzzle box. This came to be known as a Skinner box (see Figure 8-3). The animal, usually a rat or pigeon, is placed in the box. As with Thorndike’s animals, Skinner kept his animals hungry during the learning experiments. Initially, the animal would move around the cage until it pressed the lever and food would be released into the Skinner box. One advantage of the Skinner box over the puzzle box was that the animal stayed in the box and could continue learning the response.

Shaping

The first time the animal is placed in a Skinner box, it will typically move all around the box. To help it learn the relationship between pressing the lever and obtaining food, a technique referred to as shaping is used. Shaping is a process by which the animal is led to make the desired response in small steps. For example, you could initially give the animal food just by facing the lever in the Skinner box. Next, give the animal food as it moves toward the lever. Then, give it food as it touches the lever. Finally, it will press the lever and receive food.

Shaping is a common procedure used to train animals to perform any new task. Animal performances in a circus are largely the result of shaping. Even a complex performance can be broken down into discrete steps that can be learned through reinforcement. If you want to teach your dog to stand on its hind legs and turn around in a circle, you would start with teaching it to stand. You would give it a treat each time it stood until it was able to adopt this posture. You would then give it a reward for initially turning slightly. Then a reward as it turned more. In this way you can use shaping to train your dog to do new tricks. However, for shaping to be effective the reinforcement must quickly follow the desired response.

Reinforcement and Punishment

Giving a reinforcement following a particular behavior increases the likelihood that the behavior just produced will reoccur. Technically, this is referred to as positive reinforcement. In Skinner’s research, the rat presses a lever and receives a pellet of food. Following this the rat will continue to press the bar and receive food.

What if at this point you wanted the rat not to press the bar, what would you do? One thing you could do is to pair the bar pressing with something the rat did not find reinforcing. For example, if the bar press is followed by a shock, then the animal is less likely to continue pressing the bar. Technically, this procedure is referred to as positive punishment. Positive punishment decreases the likelihood that a particular response will be repeated.

The meaning of positive in the case of both positive reinforcement and positive punishment refers to something being added that changes the likelihood of a response. Positive reinforcement increases the likelihood that the response will increase. Positive punishment increases the likelihood that the response will decrease.

In Skinner’s terminology, there is also negative reinforcement and punishment. Negative reinforcement occurs when the likelihood of a behavior is increased by the removal of an event. Typically, the event is aversive to the organism. In this case removing an event changes the likelihood that it will occur. What if there was a loud noise and performing an act would stop it. All of us, including rats, would perform an act if it turned off the loud noise. The removal of the loud noise following such an act would be an example of a negative reinforcer.

Negative punishment occurs when the likelihood of a behavior is decreased by the removal of an event. What would happen, for example, if your employer quit paying you each time you did a job? Of course, you would quit doing the job. Hungry rats do the same thing in the Skinner box although it is food and not money they seek. Thus, reinforcement and punishment influence the likelihood that behaviors will be performed. As you can see in Table 8-1, positive and negative reinforcement increase the likelihood of the behavior; positive and negative punishment decrease the likelihood of the behavior. In the next section, the manner in which they are delivered will also influence an organism’s responses.

Schedules of Reinforcement

When you play a slot machine in a casino, you don’t receive money each time you play. It would be great if you did. However, if you won each time you played you would act very differently. Most likely, you would play the slot machine as fast as you could. What if the opposite happened? What if word got out that no one ever wins on a certain machine? What would you do? You would quit playing that machine. Skinner realized the same was true with his rats and pigeons. That is, Skinner realized that how reinforcers are administered can determine how behaviors are emitted.

If the reinforcement follows every operant response, it is referred to as continuous reinforcement. If the reinforcement only sometimes follows the operant response, it is referred to as partial reinforcement. Typically, continuous reinforcement is used to shape and train the animal to perform the desired response. That is, when teaching the animal to approach the lever, you give a reinforcement for each desired response. Once it has learned to press the lever for food, the animal will continue to press the bar even if food is not given for each bar press. This is a partial reinforcement schedule. Once the animal has learned the response such as bar pressing in the Skinner box, stopping all reinforcement will result in the animal no longer pressing the lever. Technically, this is referred to as extinction.

Partial reinforcement can be programmed in relation to the number of responses (ratio) the animal makes or the amount of time (interval) between responses. Skinner examined a number of these patterns, which came to be called schedules of reinforcement. The ratio and interval schedules of reinforcement can be either fixed or variable resulting in four major categories.

Using a fixed ratio schedule, the animal receives a reinforcement every certain number of times. For example, the animal could receive a reinforcement every fourth time it presses the bar. Humans who work in a factory that pays them a certain amount after producing five widgets would be paid in terms of a fixed ratio schedule. Using a variable ratio schedule, the animal receives a reinforcement in a manner that averages out to a certain number. For example, if the average was five, then the reinforcement could come after two responses and then seven responses and then after one response and then after nine responses.

Using a fixed interval schedule, the animal receives a reinforcement after a certain amount of time. For example, you could wait 30 seconds after the last reinforcement before the next reinforcement would follow a bar press. During this time, the animal could press the bar, but there would be no food given. Pain medication in hospitals is often set up to be administered only after a certain amount of time no matter how often the patient asks for it. Using a variable interval schedule, each reinforcement would vary such that the average amount of time would be constant. That is, if the average amount of time was 30 seconds, then some of the intervals would be shorter than 30 seconds and some longer (Figure 8-4).

Figure 8-4 Graphic of different schedules of reinforcement.

How do you think that these four different schedules of reinforcement would influence the rate of responding of the animal? To answer this question, imagine yourself sitting at a slot machine. How would you respond if you won every fifth time or every five seconds? You would of course pull the handle (or push the button) faster if it was a fixed ratio schedule. On an interval schedule, you would learn to wait some amount of time before you pressed the button. There are slight differences in responding as to whether the schedule is fixed or variable. However, ratio schedules produce faster and more responses than interval ones. This, of course, is known by every casino, which is why slot machines are set to variable ratio schedules of reinforcement. Assume you are reinforced when you check your social media or text messages. What schedule of reinforcement most matches your pattern of checking your iPhone or iPad?

CONCEPT CHECK

1. What roles do the terms operate, environment, and consequence play in the definition of operant conditioning?

2. One of Edward Thorndike’s two major contributions to the study of learning was the law of effect. Describe his law of effect in your own terms. Can you think of an example of this working in your own life?

3. What is the concept of shaping? How is it used in learning?

4. Differentiate among the following terms introduced by B. F. Skinner in studying operant conditioning:

a. Positive reinforcement

b. Positive punishment

c. Negative reinforcement

d. Negative punishment

5. Define the concept of a schedule of reinforcement. Why did Skinner introduce the concept? Identify the four schedules of reinforcement described in this section and describe the ways in which they are different.

Learning as Viewed through Ethology

Ethology, simply said, is the study of animals and what they do. The word itself is derived from the Greek and means manner, trait, or character. At the heart of ethology is the naturalistic observation of behavior within an organism’s natural environment. Within this field, it is assumed that behavioral processes have been shaped through evolution to be sensitive to environmental conditions. Thus, behavior can be understood only within the context of a particular environment.

One of the pioneers in the field of ethology was Konrad Lorenz (1903—1989). Since his early childhood on the outskirts of Vienna, Lorenz was interested in observing animals. After receiving a medical degree and continuing studies in zoology, Lorenz more formally studied behavioral patterns. He focused on those patterns that he considered characteristic of a species.

One of the important contributions of Lorenz to psychology was the study of imprinting. Imprinting is a built-in pattern in which birds such as ducks and geese follow an object, usually their mother, which moves in front of them during the first 18 to 36 hours after birth. In a series of now classic studies, Lorenz showed that orphaned baby birds would follow any moving organism, including Lorenz, as if it were their mother. Not only would they follow Lorenz but they would also ignore members of their own species and still later in life attempt to court humans rather than other geese. If the baby birds did not encounter a suitable object during this critical period of 18 to 36 hours, the birds would not imprint and would even show terror.

How did Lorenz understand imprinting? He suggested that imprinting and other similar phenomena worked like a lock and key. The key in this case would be the characteristics of the mother, including the manner in which the mother moved in front of the babies. The lock would be an innate brain pattern or template in which knowledge concerning the key would be encoded. Further, the lock and key would only work together for a critical period, in this case the first two days of life. More intriguing is the fact that once the imprinting has taken place, it is almost irreversible and cannot be changed.

Play as Learning

If you ask kids what they want to do, they usually answer “play.” Play is seen in all human cultures and across a variety of animal species (Burghardt, 2005; Göncü & Gaskins, 2007; Panksepp & Biven, 2012; Smith, 2005). Play, like babbling, appears to be preparation for future developmental stages, although the participants remain unaware of its future potential. They enjoy it for what it is. Play can be simple or it can be extremely complex, as when individuals take on roles and play them out. Even animals will sometimes shift roles, as when a dominant individual “loses” in order to keep the game going. Given its ubiquitous nature, especially in mammals, play is thought to be important and have profound value for the individual. That is, play helps the child learn relationship roles that will be needed in adulthood. In all species, play also is important for learning physical skills (Panksepp & Biven, 2012).

Burghardt (2005) suggests five criteria for characterizing play. The first is that engaging in play does not contribute to an organism’s survival at that moment. The second is that play is spontaneous, and something individuals engaged in voluntarily. Also, it is pleasurable and done for its own sake. The third factor is that play tends to be characterized by incomplete, exaggerated, and sometimes awkward movements. In this sense, it differs from behaviors performed in the service of more serious processes seen in adults related to survival and sexuality. Further, in some species, play is only seen in juveniles. Fourth, play occurs repeatedly in a similar form. This repetition of patterns is seen in play and games in both humans and other animals. Fifth and finally, play tends to take place when organisms are well-fed, healthy, and free from stress. It has been observed that play is one of the first types of behavior to drop out when animals are hungry, threatened, or in a difficult environment. Overall, organisms appear to have fun during play and do not engage in it if a positive emotional experience is not possible.

Play has been grouped by researchers into three types. These are rough-and-tumble play, object play, and pretend or role play. Rough-and-tumble play may look like real fighting or conflict, but it can be differentiated from these in a number of ways (Smith, 2005). First, rough-and-tumble play is usually engaged in by friends. Second, it does not begin with a threat and usually ends with other social activity. Third, the participants usually appear to be enjoying themselves. And fourth, the roles played appear to be flexible and there is sensitivity to environmental restraints.

Developmentally, rough-and-tumble play changes in focus from the elementary to high school years. In elementary school, rough-and-tumble play is centered on friendship themes. By adolescence, dominance becomes a more common theme. Strong gender differences in rough-and-tumble play are found across all cultures. It is always more males than females who engage in rough-and-tumble play. One common theory of rough-and-tumble play suggests it is preparation for later dominance challenges.

A modern example of object play is children playing with toys. Both anthropological and archeological studies suggest that object play is found in a variety of cultures across time. Unlike rough-and-tumble play, object play is engaged in equally by both males and females.

Pretend or role play is seen across cultures and often reflects tasks that the children observe their parents or elders engaging in. Since the peak period of pretend play occurs in children between 3 and 6 years of age, there is some suggestion that pretend play is related to understanding the intentions of others or theory of mind. That is to say, pretend play helps children understand what can happen and how others may react to these changes. Watching children of this age, you can observe how often these children refer to other people and how they might feel.

Observational Learning

At the beginning of this chapter, you read descriptions of how lab-reared chimps, who were not afraid of snakes initially, became fearful of snakes just by watching another chimp react with fear to a snake. This is referred to as observational learning.

Jane Goodall reported that chimps will take a stick and remove the leaves (https://www.youtube.com/watch?v=inFkERO30oM). They will then put this stick into a mound of termites, which looks like a big ant hill. The termites, which the chimps like to eat, will be attached to the stick when it is pulled out of the ground (like a termite popsicle). How do the young chimps learn to do this? They just watch the older chimps fish for termites.

Observational learning is seen across a variety of species including humans. Bottlenose dolphins learn from their mothers how to find sponges. Sponges are used to protect their snout while searching for food on the sea floor. Besides termite hunting with a stick, chimps also learn how to groom. Grooming produces both a social bond and removes bugs from the other chimps’ fur. What is interesting is that the manner of grooming learned in early life remains stable throughout their lifetime even when living in a different community (Wrangham et al., 2016).

Overall, observational learning is when an organism watches another organism perform an activity and copies it. In this sense, it is different from other types of learning. With classical or operant conditioning, the individual organism directly experiences the events. Observational learning, on the other hand, does not involve the person doing anything but watching. Observational learning is also referred to as social learning. It is seen across a number of species as an efficient way of acquiring new information including cultural transmission (Sapolsky & Share, 2004).

In psychology, observational learning was described in 1941 by Neal Miller and John Dollard (Miller & Dollard, 1941). Rather than reinforcement, the important component of observational learning is motivation. That is, if a person is motivated to learn a set of behaviors, then this can occur through observation.

One famous set of observational learning studies was performed by Albert Bandura and his colleagues in the 1960s. These came to be called the “Bobo doll” studies (Bandura, Ross, & Ross, 1961). The Bobo doll was an inflated clown. When hit, the clown would fall over and then come back to an upright position.

What Bandura did in his experiment was to bring 3-to 6-year-old children, one at a time, into the lab. The lab room contained a number of toys including the Bobo doll. In the lab was an adult who initially played with some of the toys but then began to hit the Bobo doll, kick the doll, and even hit it with a mallet. After 10 minutes, the child was taken to another room where he or she talked with an experimenter. After this, the child was taken to another room full of toys including a Bobo doll where the child could play. A control condition of the experiment was the same except that the adult did not hit the Bobo doll.

What do you think the child did on his or her own? Yes, if the adult hit the doll, the child did also. The children in the control condition showed much less aggression toward the Bobo doll. In the experimental condition, boys showed more aggression than girls. Also, children who were with an adult male showed more aggression than those with an adult female. Not only did this research show the importance of observational learning but also called into question the role of violence in the media.

Imitation Learning and Mirror Neurons

Observational learning is also referred to as imitation learning. What makes it so easy for humans and other animals to copy what is seen in front of them? At the end of the last century, Giacomo Rizzolatti and his colleagues made an important discovery that has helped to answer this question. The answer, which was found by accident, is related to neurons in your brain referred to as mirror neurons, which were described in the chapter on developmental processes.

As noted in this chapter, the basic idea for imitation learning is simple. Each time an individual sees an action done by another, the neurons in the observing person that would be involved in that action are activated. This activation in brain circuits in turn creates a motor representation of the observed action. That is, we see an action and our brain considers how we might make it ourselves, although we don’t do this consciously.

This process can explain one aspect of how imitation learning can take place. That is, by seeing something, your brain also comes to know how you can do it. Since the same neurons fire in your brain as you watch another do a task, your brain is able to create an action plan when you wish to produce the motor response. Even more important for Rizzolatti and Fogassi (2007) is that such a network puts the organism at an advantage. The advantage is not only do I understand “what” others are doing, but also “why” they are doing it. I am able to make guesses at their motivation and their plan of action. Thus, by having my brain work similarly to another’s brain, I have some understanding of what he or she is experiencing. Thus, I learn what someone is doing and how they are experiencing it. However, there are times when new learning may not take place such as when you are asleep. This is described in the box: Myths and Misconceptions: You Can Learn in Your Sleep.

Myths and Misconceptions: You Can Learn in Your Sleep

If you look on the Internet or at the ads in some magazines, you will find products that claim you can learn in your sleep. One ad suggests that we should start using our brain’s full potential and buy their products for learning while we sleep. Sleep learning has been a theme seen in television shows and in films for at least the last 50 years. Even an article on the Smithsonian magazine website (June 26, 2012) had the title “Experiments show we really can learn while we sleep.” It would be wonderful if you could learn a foreign language while you slept without effort!

Even with all the claims in the ads, research since at least the early 1900s has shown little evidence to support the idea you can learn new material in your sleep (Simon & Emmons, 1955). Often, the early studies did not actually ensure that their participants were asleep by using objective measures such as EEG. Thus, it was not possible to know if the person was really awake or asleep when the new material was played.

Possibly, one of the reasons that sleep and learning is thought of as a possibility is that there is a connection. A number of studies have shown that if you learn new material while you are awake, and then sleep, sleep will make the connections stronger. Material that was learned and then followed by sleep immediately was remembered better than that learned ten hours prior to sleep (Diekelmann & Born, 2010). Studies have also shown that allowing participants to sleep after learning new information resulted in better performance than if the participants were not allowed to sleep.

The brain is active during sleep. This activity allows a person to hear a sound or smell an odor and incorporate it into their consciousness, as seen in dreams. Playing foreign-language sounds previously learned during sleep also improved later recall (Schreiner & Rasch, 2014). However, material has to be presented outside of sleep for learning to take place. Overall, brain activity during sleep allows for material learned during the day to be incorporated and consolidated but it is a myth that totally new material can be learned during sleep.

Thought Question: What are some specific ways you can use the information in this feature to change how you study for your classes?

Learning Takes Place as Part of Life

The study of learning for much of the 20th century was about more basic forms of learning such as classical and operant conditioning. As we look across evolutionary history, it is easy to see how the mechanisms of learning are critical for life. We need to know which foods are important for us. We need to know where there is danger. We need to know which people are safe to be with and which are not. As you will see next, we come into the world ready and willing to learn a language. All children repeat what they hear and become able to create new sentences on their own. Not only humans, but also song birds repeat the songs they hear.

Although the basic principles of classical and operant conditioning are seen throughout nature, not every species can be conditioned in the same way. Some species of mice, for example, can be conditioned by pairing a sound or light with an electrical shock. However, the same is not true if the shock is paired with a taste. With humans, Little Albert could be conditioned by pairing a loud sound with an animal but not if the sound was paired with a toy. Thus, the evolutionary history of a specific species plays an important role in determining the nature of conditioning. We need to know where there is danger. We need to know which people are safe to be with and which are not. We also need to learn how to communicate with others and for that we use language.

CONCEPT CHECK

1. What is ethology? How is learning understood from the perspective of ethology?

2. Describe Lorenz’s pattern of imprinting. How is it like a lock-and-key? How is it different?

3. Why do animals and humans play? What are some ways we can know that play is happening? What are three different types of play?

4. How is observational learning different from learning through classical and operant conditioning?

5. What are some of the ways the discovery of mirror neurons by Rizzolatti and colleagues extends our understanding of learning through observation?

Language

Learning a language is something that is available to humans everywhere. In an amazing manner, a human infant can acquire any of the more than 6,000 languages present on earth. Environmental factors of course determine which languages any of us learns. Like imprinting, language learning is something that unfolds as the child develops. Skinner developed a theory of language acquisition based on reinforcement principles (Skinner, 1957). That is, a child would learn each word and its meaning and then how to create sentences. This view was criticized by Noam Chomsky who pointed out in his review of Skinner’s book Verbal Behavior that children can create sentences they have never heard as well as understand sentences they have not been exposed to (Chomsky, 1959). Thus, language could not be acquired in a response and reinforcement manner.

Knowing the mechanism of human language has been a great challenge. Speaking and understanding a language is something we all do. In fact, children around the world are able to understand and speak a language by the age of 3, and it only gets better from there. Children also know what words refer to and are able to use language to ask for what they want. It is somewhat miraculous that we speak to others without thinking about it. Unless we are going to give a public talk or are to be involved in an important interaction, we don’t prepare what we are going to say. We just say it. As humans, we understand and speak without effort. Further, speech is more than just reflecting language; it also plays an important role in our social life (Scott, 2019). In fact, people with similar linguist styles are likely to become friends (Kovacs & Kleinbaum, 2020).

Speech Processing and Vocalization in Infants

One approach to understanding human speech processing and vocalization has come through the study of the development of speech in human infants and young children (Gervain & Mehler, 2010; Skeide & Friederici, 2016). Surprisingly, the human embryo can distinguish vowels in utero although grammatical complexity is not fully mastered until at least 7 years of age. It should be noted that hearing is the first sense to be fully developed before birth. As you learned in the chapter on development, newborns were able to recognize stories such as The Cat in the Hat that were read to them in utero.

Newborn infants show surprising speech-processing abilities from birth (Gervain & Mehler, 2010). These include a preference for natural speech as opposed to non-speech sounds. Infants prefer their mother’s voice over that of other females and their native language over other languages. They are also able to distinguish function words such as it, this, in, of, and some from content words such as baby, table, eat, and happy. Further, they are able to detect acoustic cues that note the beginning and end of a word. Overall, infants by the sixth month of life are able to distinguish any sound (phoneme) in any language on earth. By 12 months of age, with changes in brain connections and networks, infants have more difficulty making these same distinctions in languages that are not their own (Kuhl, 2004).

In terms of vocalization, during the first month of life, the human infant produces a wide variety of sounds that are assumed to be precursors to speech. These sounds may be uttered in any context, when the infant is alone, when he or she is with caregivers, and so forth. By the second month, the infant produces “cooing” like sounds, especially in the context of interactions with others. Of course, throughout these periods, caregivers spend considerable time talking to the infant.

During the next three months, children expand their range of sounds to include squeals, growls, and more vowel-like sounds as their vocal cords begin to change. These “babbling” like sounds contain both consonant and vowel sounds. What is interesting is that deaf and hearing infants coo and babble at the same ages. By about 10 months of age, however, the babbling of hearing infants becomes more like their native language. Deaf infants begin to babble with their hands if they have been exposed to sign language. Finally, at about a year of age, words begin to appear in the speech of hearing infants. It has been estimated that infants understand about 50 words in their native language by year one. They also begin to lose the ability to recognize phonemes from any language other than their own. By a year and a half, children can understand about 150 words and produce about 50 words. The timeline of human speech production and perception is shown in Figure 8-5.

Figure 8-5 During the first year of human life, infants go through a series of changes in terms of speech production, which includes babbling and simple words such as “mama.” Likewise, speech perception changes from a recognition of all language sounds to those of one’s native language.

By 2 years of age, most infants have combined simple words and continue during the next year to reflect the grammatical rules of their language. Thus, they might say something like “mama eat.” By age 3, children have demonstrated implicit rules of grammar. For example, they say “cats” for more than one cat and “dogs” for more than one dog. They also apply the rule to irregular nouns and say “mouses” and “sheeps.” They use the past tense such as “kicked” and “played.” However, they also apply the “ed” rule to irregular verbs and say “goed” and “thinked.” This suggests that children acquire language in terms of rules rather than learning each specific word.

By age 4, a child is able to have conversations and demonstrate an implicit understanding of grammar. Over time, the child’s vocabulary increases such that he or she knows about 10,000 words in the first grade and 50,000 in the fifth grade. Children of about 3 years of age when listening to sentences activate brain areas in the left temporal cortex and the frontal cortex. The activation of the frontal cortex suggests that language learning by this age begins to involve top-down or more executive functioning.

Structure of Language

Language is a system of communicating with others using words that convey meaning and are combined according to the rules of grammar. When we think about language, there are at least five factors that should be considered. First, a language is regular and has rules, which we call a grammar. Second, language is productive. That is to say, there are an almost infinite number of combinations of words that a language can use to express thoughts. Third, language is arbitrary in that across languages any word can refer to anything. For example, the words “dog,” “chien,” “perro,” and “hund” all refer to the same animal but in different languages. As far as anyone can tell, there is an arbitrary relationship between words and their meanings. Fourth, languages are discrete in that sentences can be divided into words and words into sounds. And fifth, languages are linear in that words are presented one after the other. Further, for psychologists, language is special in that it can help us to describe both the internal world that we experience personally and the external world that we experience around us.

The basic sound of a language is the phoneme. If you say, “Hey, Bill” you produce five different phonemes. The sounds of “Hey Bill” are composed of two vowels and three consonants: /h/, /eI/, /b/, /I/, and /l/. When you read “Hey Bill” you know there are different words since there is a space between them. However, when you hear “Hey Bill” your brain must quickly make the distinction between sounds.

There are approximately 100 different phonemes used in all of the languages around the world. English uses approximately 40 of these phonemes. These 40 phonemes in English create about a half million words. The phoneme “ba” associated with the letter “b” is an element unto itself. As it is, it has no meaning other than the sound we process. Every infant can detect all of the 100-plus phonemes found in languages around the world. However, as we grow older, connections between neurons change with use and we lose this ability. At this point, we are limited to the phonemes in the languages we learned early in our lives. For example, languages such as Hebrew, Czech, and German do not have the “w” sound and often produce “w” and “v” as the same. In these cases, “wine” and “vine” may sound the same. Japanese does not have the phoneme associated with the “q” sound in English, and Japanese speakers find it almost impossible to make the sound of a duck in English—“quack.” Single-language Japanese speakers also have problems telling the difference between the /r/ and /l/ sounds found in “lock” and “rock” as both sounds are part of the same phoneme in Japanese. Thus, they may call a person named “Lynn” as “Rynn.” Of course, English speakers have similar problems when other languages use phonemes not found or differentiated in English.

The study of the ways phonemes can be combined in a language is called phonology. There are rules in every language for how phonemes can be put together. Even in languages that have the same phonemes, their combination may be different. For example, the phonemes /z/ and /b/ are found in both English and Polish. However, zb is allowed in Polish and not in English. For example, Zbigniew Brzezinski was a Polish American and national security advisor to President Jimmy Carter. A similar name would not be found in English.

The next level of analysis is a morpheme—the smallest meaningful unit of a language. A common example would be “ed,” which would signal past tense as in talked, or “s,” which would signal plural, as in books, or “un,” which would signal not, as in unbelievable. A word can contain a single morpheme, such as “cow,” or can be made up of multiple morphemes. For example, the word “un-believ-able” would have three morphemes, whereas the word “antidisestablishmentarianism” would contain six morphemes—anti-dis-establish-ment-arian-ism. Another morpheme such as “er” can change the meaning of the word such as farm (a place to grow food) to farmer (the one who grows food).

The next level of analysis is syntax—the structure of a sentence and the rules that govern it. Syntax describes the way we string words together. For example, one rule is that sentences must have both a noun and a verb. Different languages may differ in what these rules are. English tends to have the subject followed by a verb and then an object such as “Jim flew the airplane.” German and Japanese, on the other hand, tend to place the verb at the end of the sentence. English also tends to place the adjective before the noun, as in “white wine,” whereas Spanish and French tend to place it afterwards, as in “vino blanco” or “vin blanc.”

Finally, semantics is the study of meaning. That is, how do we understand what is being said? One important line of research has sought to determine how individuals mentally represent the meaning of what they hear and read. A critical question in the study of language has been the way in which humans are able to move between the levels of meaning and syntax. The overall structure of language is shown in Figure 8-6.

Figure 8-6 The structure of language.

Evolutionary Roots of Language across Species

We appear to be the only species that speaks. However, a variety of species, including certain marine mammals, parrots, hummingbirds, and songbirds have the ability to imitate sounds, which is necessary for the evolution of language (see Bolhuis, Okanoya, & Scharff, 2010). Other animals have distress calls to inform others of danger. Bees communicate through a dance to tell other bees the location of flowers. Further, Darwin noted the parallels between language learning in infants and song learning in birds.

At least since the writing of the French philosopher Condillac in the 1700s until the present day, scientists have noted the large gap between the types of communication patterns seen in humans as compared to those of any other species. In terms of complexity, including vocabulary, grammar, and the range of ideas that can be expressed, there is nothing like human language in other species. Humans communicate with language in a way that is different from every other species. In other species, communication systems tend to be mapped in a one-to-one manner. For example, a chickadee makes a sound directly related to the size and location of a predator. There is only one way of saying what was said. With human language, on the other hand, there are a variety of ways of conveying the same information. If there is a dangerous fire, you can say “leave,” “run,” “get out of here,” “there is a fire,” “there is danger,” and so forth.

What do other primates do to bond in social groups? The answer is grooming. By analogy, Dunbar (1996, 2003, 2004) suggested that language is to humans as grooming is to other primates. Actually, he suggests that language evolved in a series of stages with grooming at the earliest stage followed by vocal chorusing by way of bonding in a group followed by a socially focused language and finally the metaphoric and technical language we use today (Dunbar, 2003). Although we don’t pick small insects from the hairs of one another, we do gossip. It is clearly a way we bond with one another. Walk across a college campus and notice what most people are saying to one another on their cell phones. It is usually about other people and, of course, themselves.

The idea of language as grooming might also support the idea that language evolved from basic motor processes (Lieberman, 2000, 2006). This might help us think about the importance of using our hands as we talk to others. It might also suggest that language is an extension of the basic mating dances seen in a variety of species. Rather than a mating dance, we “chat someone up” as the British say. Further, language is used to convey a variety of underlying processes. For example, if we are teenagers, we may use “like” to plug gaps in our speech.

We use language to describe empathetic reasoning in which we understand another person’s experience. We also describe very abstract ideas such as freedom or democracy or even a multidimensional universe. If we are scientists we use more formal logic to rule out alternative hypotheses. The point is that language can describe a variety of both internal and external processes. It is this cumulative process that allows languages and their derivatives in terms of spoken and written forms to set the stage for culture to play a role in human history very different from that of other species. We can even be influenced by what was written thousands of years ago.

Language Learning in Animals

In the 1960s, Allen and Beatrix Gardner raised a chimp named Washoe in their home (Gardner, Gardner, & van Cantfort, 1989)—their single-story, brick home in the suburbs of Reno, Nevada with a fairly large backyard. Washoe was named for the county in which Reno is located. She was born in Africa and brought to the United States when she was about 10 months old. Washoe was raised as if she were a deaf child and used the American Sign Language. She actually wore clothes and shoes as well as learned to use a spoon and a cup. She learned to dress and undress herself and even use the toilet. Washoe had children’s toys and was fond of dolls. She was very interested in household tools and learned to use a hammer and screwdriver. She also liked to look at magazines. Her home was a used house trailer parked behind the house. The trailer itself contained the same furniture used by the previous owners. Someone checked on Washoe every night and an intercom allowed others to know what was happening in the trailer.

She was with adults who both used sign language with one another and with her. By the end of her first year with the Gardners, she knew about 50 words in sign language. Her level of sign language equaled human infants who lived in a household in which sign language was used. Additionally, she began to construct phrases of two or more signs. After about five years, Washoe’s vocabulary was about 140 words. She continued to combine these into meaningful phrases. She would sign, “YOU ME GO OUT.” She called her doll “BABY MINE” and the sound of a barking dog “LISTEN DOG.” The refrigerator was signed “OPEN EAT DRINK.” And like human children she would say, “COOKIE MORE.” At one point, she dropped a toy down a space in her trailer when another assistant was taking care of her. When Allen Gardner came to the trailer, she signed “OPEN” at the place where the toy had fallen behind the wall. She also signed “WATER BIRD” when seeing ducks on a pond. This suggests that Washoe was doing more than just repeating signs she had learned.

The work with Washoe and other primates has raised many questions about the nature of language, which are still being debated. However, there exist some common traits across many species (Jarvis, 2019). For example, a number of species can learn specific sounds, such as the ability of your dog to respond to commands or songbirds to seek mates. One suggestion is that there is a similarity in terms of genes and brain connections across many species (Jarvis, 2019). Across all primates, humans show greater linguistic abilities than any other species. At about age 2, human infants show an increased learning of language not seen in Washoe. In comparison, a human first grader would know about 10,000 words, which would increase to 50,000 by the fifth grade. As an adult, you will have about 75,000 words in your vocabulary.

What Is Language?

What is the function of language and how did it evolve? Darwin viewed language as the result of an evolution that began with inarticulate cries, gestures, and expressions, as seen across a variety of species followed by a series of steps in which humans moved to an articulated language. Indeed, one hypothesis suggests that a common origin for vocalization evolved more than 400 million years ago in fish. We usually do not think of fish vocalizing, but some are able to do so with the aid of an air sac that is used for buoyancy. Using muscles associated with the air sac, these fish are able to vibrate it in such a way that it functions as a resonance chamber and amplifies sound. These vocalizations are related to mating and defense of their territory.

Researchers have been able to examine the brain circuits related to these sounds in fish (Bass, Gilland, & Baker, 2008). What is intriguing is that the organization of these circuits is consistent with vocal systems in frogs, birds, and mammals, suggesting a common body plan for vocalization. The relation of this type of social vocalizations to speech in humans is still being determined.

In the 1960s, Noam Chomsky helped to establish many of the ideas and debates that today influence how we think about language. He suggested that all humans have a set of innate principles and parameters, which he called “Universal Grammar.” Universal grammar describes the total range of morphological and syntactic rules that can occur in any language. The original goal for Chomsky was to describe the manner in which spoken language is mapped onto meaning. The actual spoken words with their grammatical structure is called surface structure, whereas the meaning of the speech is called deep structure. As illustrated previously with the example of there being a dangerous fire, there are a variety of ways (surface structure) of saying this that would convey the same meaning (deep structure). An extension of this idea is shown with bilingual individuals who often will remember an event or idea but cannot remember in which language they learned about the event. Thus, Chomsky was interested in describing the rules in which deep structure meaning is transformed to language and vice versa.

One important idea is that language is generative. The basic observation is that we can generate sentences we have never uttered before as well as understand sentences we have never heard before. Children by the age of 3 are fluent speakers of their language without any formal instruction in the nature of grammar. Even more impressive is their ability to invent languages that are more systematic than the ones they hear and to follow subtle grammatical principles for which there are no examples in their environment (Pinker & Bloom, 1990).

Stop for a second and listen to what you say to your friends. Each time you speak, you generally use a sentence you have never used before. Sure, the meaning is similar to other times you have spoken, but the exact wording is different. Without thinking, you produce the sentences and you understand the sentences. What is more, you extract meaning even when there is ambiguity. “Flying planes are dangerous” is simple for humans to understand but difficult for a computer given the ambiguous nature of the sentence. This is not unlike, “Time flies like an arrow; fruit flies like a banana.” There is also the REO Speedwagon album You Can Tune a Piano but You Can’t Tuna Fish. Ambiguity is something humans do well given the context of the interaction in which the statement is made. Further, we extract meaning from language in a way that is not always logical, as in the famous, “We park in a driveway and drive on a parkway.”

It has been suggested by a variety of authors that the expanded childhood of humans sets the stage for language learning. That is to say, the longer contact of the human infant with its family and the need for complex communication would support the development of language. In fact, brain-imaging studies show that before infants have produced their first words, they have already learned critical sound patterns of the language they will speak. From there, language learning explodes. Children in elementary school talk to one another and share their needs and moods with others. This in turn is followed by a period of adolescence with the pressures of social interactions (Locke & Bogin, 2006). Surprisingly, a variety of research studies from numerous cultures suggests that one main topic of language is social relationships—generally referred to as gossip. What do you talk to your friends about? The answer is usually other people. In this sense, one function of language is to keep the connection in social relationships.

Although children learn to speak a language and use the rules of grammar so quickly, Chomsky was not convinced that language could be explained by Darwin’s understanding of evolution. For Chomsky, language may have appeared as our brains became larger and more complex. Thus, language learning was not a product of natural selection but an emergent property of brain complexity. Chomsky rejected language being influenced by natural selection and suggested it has not evolved in any significant way in the last 100,000 years (Berwick, Friederici, Chomsky, & Bolhuis, 2013). Overall, Chomsky sees language facility as an inborn ability and refers to language learning in humans as the innate Language Acquisition Device or LAD.

One language researcher who does see language as shaped by natural selection is Steven Pinker. Pinker (1994) begins with the suggestion that the process of language learning must be innate. In this way, language can be considered as any sensory process or instinct whose development can be viewed from an evolutionary perspective. In fact, Pinker suggests that language reflects the same type of design features as physical structures such as the eye. Since it is difficult to compare the development of language in humans with other species, one alternative is to compare typical language development in humans with impaired language development (van der Lely & Pinker, 2014).

What is especially intriguing to Pinker is that in learning a language, parents give children examples of language through their speech, but do not teach rules per se. However, children are able to infer the rules and apply them automatically. One example of this in English is when children say “he run-ed” or “she go-ed” rather than “he ran” or “she went.” Clearly the child is applying a past-tense rule rather than just repeating what his or her parents said. The fact that children apply such language rules suggests innate mechanisms for language learning based on universal principles rather than just copying what a parent says. In this sense Pinker asks us to look to biological predispositions rather than culture in order to understand language learning.

Over the years, it has been argued by such researchers as Alvin Liberman that speech is special. That is to say, humans are able to recognize certain sounds used in human speech in ways that other species cannot. However, other research has suggested that certain other species are able to make these discriminations. This would suggest that the ability to perceive speech-like sounds predates the evolution of language in humans. The picture is complicated by the fact that humans use different areas of their brains for perceiving speech versus other auditory sounds. In fact, there is a certain type of brain damage called pure word deafness in which a person can hear environmental sounds but not analyze speech (Maffel et al., 2017). There is also the opposite condition in which a person can analyze speech but not recognize environmental sounds.

If language is special for humans, what aspects of language represent this specialness? We know that human infants raised in an environment in which they are introduced to language will begin to communicate and show all the aspects of language generally before age 3. We also know from some tragic situations that human children raised without exposure to language will never develop normal language abilities. It is also clear that other species do not develop the major aspects of human language in the wild. The question arose as to what would happen if a chimpanzee—who is our closest genetic relative—was reared in an environment in which language was present.

As described previously, Allen and Beatrix Gardner raised a chimp named Washoe in their home. She was raised as if she were a deaf child using American Sign Language. By the end of her first year with the Gardners, she knew about 50 words in sign language. After about five years, Washoe’s vocabulary was about 140 words. In the 1980s, Sue Savage-Rumbaugh took a somewhat different approach to teaching communication to a bonobo, also referred to as a pygmy chimpanzee. This bonobo was named Kanzi. What was really interesting was that Kanzi learned his first words by watching the researchers try to teach his mother language. He actually displayed knowledge of words without ever being asked. The idea with Kanzi was to teach him to communicate. Like Washoe, Kanzi played with toys and was involved in conversations taking place around him. He was also taken on walks around the research center on which he was spoken to. However, this time the conversations were in spoken English and not sign language. There are a number of videos showing Kanzi responding to such English sentences as “Take off Sue’s shoe” by performing the requested action. Also, Kanzi could respond by pointing to symbols. Each symbol represented an English word. Given Kanzi’s ability to perform acts and respond to English questions, many researchers suggest he was able to understand sentence structure. For example, he was correct 75% of the time when given sentences like “place the book on the rock” as opposed to “place the rock on the book.” However, he had more of a problem when asked to do two activities such as “give Sue the bottle and the cup.” He could do one but not both. Like Washoe, Kanzi’s comprehension of language appears to be fixated to that of a child aged 2 and a half. If you want to see pictures of Kanzi as an adult, you can go to the Internet (http://www.npr.org/templates/story/story.php?storyId=5503685). If you would like to hear a TED Talk by Dr. Savage-Rumbaugh about primate language, you can go to the Internet (https://www.ted.com/talks/susan_savage_rumbaugh_the_gentle_genius_of_bonobos and http://www.ted.com/talks/susan_savage_rumbaugh_on_apes_that_write.html). The research involving primate language suggests that basic linguistic abilities of some form existed before the evolution of human speech. What allowed humans to develop speech and move beyond the level of a 2-year-old child is still a hotly debated question (see Deacon, 1997; Lieberman, 2000 for overviews). You can also think about what your dog hears in the box: Real World Psychology: Do Dogs Know Words?

Real World Psychology: Do Dogs Know Words?

Anyone who knows someone with a dog has observed that person speaking to the dog, often in complete sentences. You may have even observed the dog respond to commands. In fact, research suggests that dogs can respond to at least 1,000 words. That is, they can bring back a ball rather than a stick if commanded. But what does the dog hear? Does it know that words are being spoken or just wag its tail when its owner smiles and pets it? For years we could have our opinion, but there was little research as to what was actually going on in the brain of a dog when it hears human speech.

Attila Andics and his colleagues sought to answer this question (Andics, Gábor, Gácsi, Faragó, Szabó, & Miklósi, 2016). First, the dogs were trained to lie still in a brain-imaging fMRI machine. Although the dogs could move and leave whenever they wanted, they tended to lie still in the fMRI as they do in their homes on their bed or rug. Prior to the experiment, voice commands from a trainer were recorded. This trainer had worked with each of the dogs in the experiment. The experiment manipulated the meaning of the word presented and the emotional intonation in which it was presented. That is, a word could be presented that either had meaning as a praise word or not. The word could also be presented in a neutral manner or one with emotional feeling.

What these researchers found was that praise words presented in both a neutral and emotional manner activated the dog’s left hemisphere. Neutral words did not activate the left hemisphere in the same manner. This suggests that the dogs can distinguish words related to praise from those that are not. When looking at the emotional intonation of the praise and neutral words, fMRI results showed that it was processed in a different part of the brain. Thus, meaning and emotion are processed independently in different parts of the dog’s brain. From a complete analysis of the data, the research concludes that dogs rely on both word meaning and emotional intonation when determining the reward value of the phrase. Overall, dogs are able to link the sounds of human speech to basic meaning. On a research level, the study also shows that it is possible to study brain activation in awake animals.

Thought Question: What do you think the results would be if you could repeat this experiment with a chimpanzee or a bonobo or other animal? What about with a human infant?

Structure of Vocal Cords

The structure of our vocal cords is one important aspect of our ability to speak. How do humans make sounds that we hear as speech? We do it with our larynx, which also contains a cartilage we call our Adam’s apple. If you feel your Adam’s apple, you realize it is in your neck well below your mouth. By having your larynx low in your throat, you are able to make a wider range of sounds than other species can produce. To make a sound, the vocal cords in our larynx move in and out, modifying the continuous flow of air from our lungs into puffs of air. We also use our tongue to modify speech sounds. Notice how your tongue is in different places when you say “to” as opposed to “shoe.” Although we will not go into details here, what we hear is also related to spacing between the basic sounds we produce (Lieberman, 2006).

Most other primate species have the larynx higher in the throat. This allows them to breathe and drink at the same time but not to make speech sounds. The human infant actually begins life with the larynx high in the throat. This also allows for breathing and drinking at the same time. That is, human infants like other mammals are able to ingest air and liquid at the same time. In about the third month of life as human infants develop, their vocal tract begins to descend so they can begin to produce a unique set of vowels. Such vowels allow us to make differential sounds as would be found in words such as see, saw, and sue. Also, humans have a larger area of the spinal cord necessary for breath control in producing speech compared to other primates as well as an auditory system tuned to the predominant frequencies found in speech. It has also been noted that during the first year of life, the human face changes from one with the features found in Homo erectus and Neanderthals to that of modern humans (Lieberman, 2006). From the first year to about 6 years of life, our tongues gradually descend into the pharynx. This change allows us to make a wider variety of sounds that make up our languages. But also, as Darwin noted, this increases the likelihood of choking in humans as compared to other primates.

CONCEPT CHECK

1. What evidence can you point to to conclude that the chimpanzee Washoe was capable of going beyond just repeating signs she had learned?

2. What are the evolutionary stages Dunbar and Lieberman suggest language went through, beginning with grooming and basic motor processes respectively?

3. What are some critical factors to consider in defining what language is?

4. Define the following terms that are important aspects of the structure of language:

a. Phoneme

b. Phonology

c. Morpheme

d. Syntax

e. Semantics

5. What did language researcher Noam Chomsky mean by the following terms: universal grammar, surface structure, and deep structure? How were these concepts related?

6. What does it mean when we say that language is generative? Give an example.

7. If language is special for humans, what aspects of language represent this specialness? How does the research with the chimpanzee Washoe and the bonobo Kanzi relate to this question?

8. What are the parts of the structure of the vocal tract that are important to human vocalizing? What benefit does that provide humans versus other primate species in the development of language?

Language, Genes, and the Brain

The traditional model of language processing in the brain dates back to the 1800s. The French neurologist Paul Broca had a patient who had a stroke. The damage to the brain resulted in the patient having difficulty in producing speech, but not in understanding it. This type of language disorder has come to be called Broca’s aphasia, and the left frontal area of the brain affected, Broca’s area. In 1887, about 25 years after Broca described his patient, the German neurologist Carl Wernicke described the opposite condition in which a person could produce speech, but it lacked coherent meaning. This disorder came to be called Wernicke’s aphasia and the left posterior area generally affected in the brain as Wernicke’s area (Figure 8-7). The term aphasia refers to the loss of ability to understand or express certain aspects of speech related to damage in the brain.

Figure 8-7 Brain areas involved in language.

The basic idea is that spoken language is first perceived in Wernicke’s area, which is related to the processing of auditory information. This information is then transmitted by pathways to Broca’s area. Broca’s area is related to speech production. Studies from individuals with some form of brain damage suggest that Broca’s area is involved in not only the production of speech but also syntax, which includes grammatical formations involving verbs. Individuals with damage in Wernicke’s area do not have similar problems producing speech, but with those aspects related to the meaning of the words, especially nouns.

More recent brain-imaging studies have asked individuals either to read or to repeat spoken words. These studies show brain activation in the individual’s left hemisphere in those areas associated with motor responses, such as the primary motor cortex, the premotor cortex, and the supplementary motor cortex as well as areas in both hemispheres around Broca’s area.

Philip Lieberman (2000, 2006) cautions against seeing language as encapsulated in just Broca’s and Wenrnicke’s areas. He has described the evolution of language in terms of its connections with early motor processes, especially subcortical structures such as the basal ganglia. Lieberman further notes that most language disorders include these subcortical structures along with Broca’s and Wenrnicke’s areas. In addition to specific brain areas that are activated during language tasks, there are extensive networks of brain connections (Fedorenko & Thompson-Schill, 2014; Hagoort, 2019; Pylkkänen, 2019). Figure 8-8 shows the areas of the brain activated during different types of language tasks.

Figure 8-8 Specific brain areas seen to be activated during language-related tasks. These areas include those involved in understanding meaning (red—high-level language regions), speech perception areas (yellow), reading areas (vWFA—green), speaking areas (purple—articulation regions), and those areas involved in problem solving (blue—cognitive control regions).

If you think about understanding and speaking language, you quickly realize there are a large number of separate tasks that add to the complexity of language. A number of these take place out of our awareness as we put together the information available to us. What we see can actually influence what we hear. One simple example is referred to as the McGurk effect. You can see this on the Internet (https://www.youtube.com/watch?v=G-lN8vWm3m0). Just changing the way someone moves his lips determines which sound we hear. All of this takes place out of our awareness.

During the decades of brain-imaging studies examining the nature of language, consistent findings have emerged. For example, there is a group of regions in the brain that represents information about the meaning of language (Huth et al., 2016). These regions are referred to as the semantic system and are sensitive to natural speech and its meaning. The overall semantic system involves brain areas in the temporal, parietal, and prefrontal areas. Within the larger systems more specific areas are sensitive to language features, such as nouns, action verbs, and social narratives. Other areas are utilized in the understanding of related concepts such as living things, tools, food, or shelter. This suggests that language information is organized in terms of categories. Most of the research involves one’s first language but more recent studies involved a second language as described in the box: Applying Psychological Science: Learning a Second Language.

Applying Psychological Science: Learning a Second Language

There are some 6,000 languages in the world. Some of us spend our lives speaking only one, whereas others can speak a number of languages. In fact, it has been estimated that more than half of the world’s population can speak more than one language (Grosjean, 2010). Knowing more than one language can often be an accident of location. For example, citizens of Europe often speak the language of their country, as well as those of neighboring countries. English may also be present as it represents both the language of science and a common language across European countries. In fact, more than half of the population of Europe is bilingual. In the United States, about 20% of people speak a language other than English at home. This percentage increases in major cities.

Learning two or more languages can occur in a number of different situations. Some individuals learn two languages from birth. It is somewhat surprising that infants are able to learn two languages with apparent ease. For example, infants learning Japanese have to learn that articles and prepositions come after nouns, whereas in English they come before. Thus, if the same infant were to learn both Japanese and English, then he or she would need to know two sets of phonemes, two sets of words, and two grammatical systems. Even before the first 6 months of life, infants are able to differentiate two different languages (Costa & Sebastián-Gallés, 2014). Infants are also able to differentiate languages by the gestures that native speakers make.

Others learn a second language at a later time as with people who were brought to another country as children. Both learning a second language from birth and or as a young child appears not to be a difficult task. Although still under some debate, learning a second language after puberty requires more effort. However, those who learn a second language later in life still show brain changes.

As with learning any new task, we can expect brain changes in learning a new language. Unlike learning to juggle or navigate the roads of London, learning a second language results in different areas of your brain being changed (Li, Legault, & Litcofsky, 2014). Additionally, the age of the second language acquisition is related to cortical activation (Wei et al., 2015). Both those who learn a second language early and later in life show changes in different brain activations than those who learn only one language. However, there is more variability in the results of those who learn the second language later in life.

One task for a person who is bilingual is to choose which word to use. If you see a piece of fruit do you say “apple” or “manzana” (Spanish). Although similar brain structures may be involved in processing both languages, it is not surprising that those areas of the brain related to cognitive control would show different activation in those who speak one versus two languages (Sulpizio, Del Maschlo, Fedeli, & Abutelebi, 2020). Specifically, bilingual individuals show more activation of the left frontal areas of the brain during comprehension tasks than those who speak one language. Bilingual individuals also show more activity in left hemisphere language related brain areas. Further, bilingual individuals also show more white matter in brain areas associated with verbal speech production. Additionally, greater volume in the corpus callosum, an area involved in transferring information between the hemispheres of the brain, is seen in bilingual individuals (Felton et al., 2017). Interestingly, bilingual individuals also show more of an ability to switch between tasks, even nonlinguistic ones, than those who speak only one language. Figure 8-9 shows areas of the brain related to language and cognitive control. It should be noted that at one time school administrators in the US discouraged teaching a second language in elementary schools because of interference between the two languages. We now know that bilingual individuals can switch between languages with ease (Kleinman & Gollan, 2016).

Figure 8-9 Areas of the brain related to cognitive control and language.

Source: Abutalebi and Green (2007).

If learning a second language changes brain activation and increases cognitive control throughout one’s life, is this related to cognitive changes in aging? Some studies are beginning to suggest the answer is yes. It is suggested that those who know two languages have an advantage in switching tasks, sustaining attention, and memory processes (Bialystok, 2017; Bialystok, Craik, & Luk, 2012). Additionally, bilingual individuals who develop cognitive and memory problems associated with aging such as Alzheimer’s do so three to four years later than those who speak a single language.

Thought Question: You have just been asked to develop a new language curriculum for your home school district. Given what you have just read about learning more than one language, what suggestions would you make in your initial proposal?

Reading

Although language is something that we as humans do naturally, we have to actively learn to read (Dehaene & Dehaene-Lambertz, 2016). As humans, we have only been reading for about 5,000 years. It would take another 1,000 years for us to develop a formal alphabet. One important brain area related to reading is referred to as the visual word form area (VWFA). This area is located near the bottom of the brain where the temporal lobe and occipital lobe come together. This area activates whenever we see a written word. It does not show activation in those individuals who cannot read or in response to objects or faces. The VWFA is also located close to the area that responds to faces (fusiform face area—FFA) and the area that responds to places. Activation of the visual word area is only seen after a child learns to read.

Evolution of Language

In terms of evolution of language, there has been a debate as to whether it arose gradually over time or arose very quickly with the anatomical changes that give humans linguistic abilities (see Corballis, 2017; Ghazanfar, 2008 for overviews). In a variety of human traits such as color vision, there is clear evidence for a gradual evolution. However, others have argued that language is totally human and happened quickly.

Although the question is not completely settled, brain-imaging studies are beginning to suggest a gradual development of language. For example, James Rilling and his colleagues examined the differences in the way fiber tracts go between the frontal and temporal lobes in humans and other primates (Rilling et al., 2008). This is an important pathway in the brain for language. Damage to this pathway in humans leaves the person with the ability to understand speech but not to be able to repeat what was said.

Language and Genes

Since the writings of Darwin, the evolution of language has been a topic of debate. However, understanding the relationship of genes and language has been difficult (Fisher & Marcus, 2005). One approach has been to study those individuals who show language disorders from a genetic perspective. There is a rare language disorder that is inherited and has been linked to an allele of the FoxP2 gene on chromosome 7. Humans with this allele show problems in articulation, production, comprehension, and judgments related to grammar. The normal version of the gene is found universally in humans, but not in other primates. However, the gene is found in songbirds and has been related to song production. In humans, the gene is related to vocal learning and the integration of auditory and motor processes. Some estimates suggest that this gene appeared within the last 200,000 years. At present this research is in the early stages and there is controversy concerning the exact genetic basis of language.

CONCEPT CHECK

1. What are the primary contributions of the following researchers to our understanding of language processing in the brain:

a. Pierre-Paul Broca?

b. Carl Wernicke?

c. Philip Lieberman?

d. Skeide and Friederici?

e. Alexander Huth?

2. What evidence would you cite to show that reading (processing visual language) is different from processing verbal language in the brain?

3. Did human language evolve gradually over time or very quickly? What evidence can you cite to support your answer?

4. At this point in time, what can we say about the genetic basis of language using the example of the FoxP2 gene on chromosome 7?

Summary

Learning Objective 1: Describe the basic processes of classical conditioning

Classical conditioning was first described at the turn of the last century by the Russian physiologist Ivan Pavlov. Classical conditioning is the process in which two stimuli become associated with each other. One of these stimuli, such as food, will produce a natural response, such as salivation. In this case, salivation is referred to as the unconditioned response (UCR). Because the food stimulus will consistently produce a response, it is referred to as an unconditioned stimulus (UCS). Classical conditioning can work with any naturally occurring physiological process. The principles of classical conditioning work equally well both with emotionally positive and negative stimuli.

In studies of classical conditioning, it was noted that events that happened at about the same time as an unconditioned stimulus could themselves produce a response. After a time, the events alone will produce salivation. These types of events are referred to as conditioned stimuli (CS). Technically, we say that if the unconditioned stimulus is paired with another stimulus, the conditioned stimulus, then after a number of times of pairing, the conditioned stimulus alone will produce the natural response. This response is referred to as a conditioned response (CR). The process of pairing a UCS and a CS is referred to as acquisition. Extinction (absence of the CR) happens when the CS is repeatedly presented alone without the UCS. Spontaneous recovery (of the CR) can happen after the CS is again presented after a time delay.

Scientists have used the principles of classical conditioning to understand the experiences of those who use drugs. Initially, professionals were surprised to see physiological changes as the person was only preparing to take the drug. Even stranger was that the person showed reactions that were opposite to the normal effects of the drug. We now know that these opposite responses were the body’s way to prepare for the negative effects of the drug.

Phobias can be the result of simple conditioning. John Watson worked with a normal 9-month-old child named Little Albert. Initially, Little Albert was conditioned by pairing a white rat and a loud noise. After this, any furry animal such as a rabbit would produce the same fear response. This is referred to as generalization.

A type of learning that does not follow simple conditioning procedures is food aversion. One of the early researchers in the 1950s to study taste aversion was John Garcia. In fact, the phenomenon of taste aversion is often referred to as the Garcia effect. From an evolutionary perspective, this is a critical mechanism. To learn quickly that a food is bad for you could prevent you from experiencing a number of trials until you learned that a certain food was bad for your health.

Robert Ader was able to show that the immune system, like other physiological systems, could be classically conditioned. Dating back to Russian studies in the 1920s, it has been shown that immune system responses such as antibody production could be conditioned. That is, if a drug that produced these responses was paired with a neutral stimulus as in normal classical conditioning, the neutral stimulus alone could produce the immune system response.

We habituate to a repeated stimulus because its repeated occurrence carries with it no new information. The first time we experience it, it could be signaling danger or other information important to our existence. We may need to adapt to protect ourselves. However, once we know we are not receiving new information, there is no need to respond. This is part of our evolutionary history in which organisms use their energy for events that are important and reduce their energy expenditure for those that are not. Habituation is thus a natural response for regulating our cognitive and emotional energy. The opposite of habituation is sensitization.

Learning Objective 2: Describe the basic processes of operant conditioning.

Operant conditioning, also called instrumental conditioning, is the type of learning in which the frequency of the behavior is controlled by its consequences. The behaviors that an organism performs is referred to as operant responses. The term operant is the combination of two terms, operate and environment. Thus, they are behaviors that operate on the environment to produce consequences. In the case of your dog, the behavior may be a trick and the consequence may be receiving food.

Thorndike formulated his law of effect. That is, when the cat made a response that led to the opening of the door and food (the satisfying effect), then the cat would be more likely to perform that same response again. The opposite is also true. If the response produces discomfort, then those responses will be reduced. The second way Thorndike influenced the study of learning was to graph the animal’s response, which is referred to as a learning curve.

B. F. Skinner was the person who most influenced the study of learning in psychology during the middle of the last century. Skinner coined the term operant behavior to refer to the behavior that an organism produces that influences its environment. If the behavior (for example, pressing the bar) is reinforced (for example, receiving food), then its occur-rence will increase. In order to study learning, Skinner developed a simplified version of Thorndike’s puzzle box. This came to be known as a Skinner box. One advantage of the Skinner box over the puzzle box was that the animal stayed in the box and could continue learning the response.

Reinforcement and punishment influence the likelihood that behaviors will be performed. The meaning of positive in the case of both positive reinforcement and positive punishment refers to something being added, which changes the likelihood of a response. Positive reinforcement increases the likelihood that the response will increase. Positive punishment increases the likelihood that the response will decrease. In Skinner’s terminology, there is also negative reinforcement and punishment. In this case removing an event changes the likelihood that it will occur. Negative reinforcement occurs when the likelihood of a behavior is increased by the removal of an event. Typically, the event is aversive to the organism. Negative punishment occurs when the likelihood of a behavior is decreased by the removal of an event.

Skinner realized that how reinforcers are administered can determine how behaviors are emitted. If the reinforcement follows every operant response, it is referred to as continuous reinforcement. If the reinforcement only sometimes follows the operant response, it is referred to as partial reinforcement. Typically, continuous reinforcement is used to shape and train the animal to perform the desired response.

Learning Objective 3: Summarize the types of learning that occur during imprinting, play, observational learning, and imitation learning.

Ethology is the study of animals and what they do. At the heart of ethology is the naturalistic observation of behavior within an organism’s natural environment. Ethology assumes that behavioral processes have been shaped through evolution to be sensitive to environmental conditions. Thus, behavior can be understood only within the context of a particular environment. One of the pioneers in the field of ethology was Konrad Lorenz. One of the important contributions of Lorenz to psychology was the study of imprinting. Imprinting is a built-in pattern in which birds such as ducks and geese follow an object, usually their mother, which moves in front of them during the first 18 to 36 hours after birth.

Play is seen in all human cultures and across a variety of animal species. Play appears to be preparation for future developmental stages, although the participants remain unaware of its future potential. They enjoy it for what it is. Play is thought to be important and to have profound value for the individual. That is, play helps the child learn relationship roles that will be needed in adulthood. In all species, play also is important for learning physical skills.

Observational learning is when an organism watches another organism perform an activity and copies it. In this sense, it is different from other types of learning. With classical or operant conditioning, the individual organism directly experiences the events. Observational learning, on the other hand, does not involve the person doing anything but watching. Observational learning is also referred to as social learning. It is seen across a number of species as an efficient way of acquiring new information. Observational learning is also referred to as imitation learning. That is, we see an action and our brain considers how we might make it ourselves, although we don’t do this consciously.

Although the basic principles of classical and operant conditioning are seen throughout nature, not every species can be conditioned in the same way. The evolutionary history of a specific species plays an important role in determining the nature of conditioning. As we look across our own evolutionary history, we can see how the mechanisms of learning are critical for our lives. We need to know which foods are important for us. We need to know where there is danger. We need to know which people are safe to be with and which are not. We come into the world ready and willing to learn a language.

Learning Objective 4: Describe the process of how we learn a language.

Learning a language is something that is available to humans everywhere. In an amazing manner, a human infant can acquire any of the more than 6,000 languages present on earth. Environmental factors of course determine which languages any of us learns.

The human embryo can distinguish vowels in utero although grammatical complexity is not fully mastered until at least 7 years of age. Infants prefer their mother’s voice over that of other females and their native language over other languages. By the sixth month of life, infants are able to distinguish any sound (phoneme) in any language on earth. By 12 months of age, infants have more difficulty making these same distinctions in languages that are not their own (Kuhl, 2004). In terms of vocalization, during the first month of life, the human infant produces a wide variety of sounds that are assumed to be precursors to speech. By the second month, the infant produces “cooing” like sounds, especially in the context of interactions with others. It has been estimated that infants understand about 50 words in their native language by year one. They also begin to lose the ability to recognize phonemes from any language other than their own. By a year and a half, children can understand about 150 words and produce about 50 words. By two years of age, most infants have combined simple words and continue during the next year to reflect the grammatical rules of their language. By age 3, children have demonstrated implicit rules of grammar. By age 4, a child is able to have conversations and demonstrate an implicit understanding of grammar. Over time, the child’s vocabulary increases such that he or she knows about 10,000 words in the first grade and 50,000 in the fifth grade.

Language is a system of communicating with others using words that convey meaning and are combined according to the rules of grammar. When we think about language, there are at least five factors that should be considered. First, a language is regular and has rules that we call a grammar. Second, language is productive. That is to say, there are an almost infinite number of combinations of words that a language can use to express thoughts. Third, language is arbitrary in that across languages any word can refer to anything. Fourth, languages are discrete in that sentences can be divided into words and words into sounds. And fifth, languages are linear in that words are presented one after the other. Further, for psychologists, language is special in that it can help us to describe both the internal world that we experience personally and the external work that we experience around us.

The basic sound of a language is the phoneme. The study of the ways phonemes can be combined in a language is called phonology. The next level of analysis is a morpheme—the smallest meaningful unit of a language. The next level of analysis is syntax—the structure of a sentence and the rules that govern it. Syntax describes the way we string words together. Finally, semantics is the study of meaning. That is, how do we understand what is being said?

Learning Objective 5: Identify the parts of the brain that are active in language.

Spoken language is first perceived in Wernicke’s area, which is related to the processing of auditory information. This information is then transmitted by pathways to Broca’s area. Broca’s area is related to speech production. Studies from individuals with some form of brain damage suggest that Broca’s area is involved in not only the production of speech but also syntax, which includes grammatical formations involving verbs. Individuals with damage in Wernicke’s area do not have similar problems producing speech, but with those aspects related to the meaning of the words, especially nouns.

Recent brain-imaging studies have shown brain activation in the individual’s left hemisphere in those areas associated with motor responses, such as the primary motor cortex, the premotor cortex, and the supplementary motor cortex as well as areas in both hemispheres around Broca’s area.

Study Resources

Review Questions

1. This chapter starts out by saying, “Although most of us have an idea of what it means to learn something, it is actually a difficult and complex concept to define. In fact, it has been pointed out that the definition of learning differs across different areas of study including psychology.” Now that you’ve finished the chapter, how would you define learning?

2. What contributions have the following researchers made to their specific types of learning as well as to our understanding of learning as a whole:

a. Classical conditioning: Ivan Pavlov, John Watson, John Garcia, Robert Ader, Eric Kandel, Joseph Wolpe

b. Operant conditioning: Edward Thorndike, B. F. Skinner

c. Learning from the perspective of ethology including play: Konrad Lorenz, Gordon Burghardt, Neal Miller and John Dollard

d. Observational learning—Albert Bandura, Giacomo Rizzolatti, and Leonardo Fogassi

3. In this chapter we have seen many examples of research into all types of learning with both animals and humans. Considering each of these types of learning—classical conditioning, operant conditioning, play, and observational learning—identify how you have used each of them in the past in your own learning. How might you use each of them in the future?

4. Describe the structure of language.

For Further Reading

✵ Eibl-Eibesfeldt, I. (1989). Human Ethology. New York: Aldine de Gruyter.

✵ Lorenz, K. (1981). The Foundations of Ethology. New York: Springer-Verlag.

✵ Pinker, S. (1994). The Language Instinct. New York: William Morrow & Co.

✵ Pinker, S. (2007). The Stuff of Thought: Language as a Window into Human Nature. New York: Viking.

Web Resources

✵ Jane Goodall—https://www.youtube.com/watch?v=inFkERO30oM

✵ Kanzi—http://www.npr.org/templates/story/story.php?storyId=5503685

✵ Primate language—https://www.ted.com/speakers/susan_savage_rumbaugh and http://www.ted.com/talks/susan_savage_rumbaugh_on_apes_that_write.html

Key Terms and Concepts

acquisition

aphasia

classical conditioning

conditioned response (CR)

conditioned stimuli (CS)

continuous reinforcement

deep structure

extinction

fixed-interval schedule

fixed-ratio schedule

generalization

generative

habituation

imitation learning

imprinting

law of effect

morpheme

negative punishment

negative reinforcement

observational learning

operant behavior

operant conditioning

partial reinforcement

phoneme

phonology

positive punishment

positive reinforcement

reinforcement

schedules of reinforcement

semantics

sensitization

shaping

spontaneous recovery

stimulus generalization

surface structure

syntax

unconditioned response (UCR)

unconditioned stimulus (UCS)

universal grammar

variable-interval schedule

variable-ratio schedule